Telephone-operator&#39;s equipment.



W. G. BLAUVELT & E. G. MOLINA.

TELEPHONE OPBRATOBS EQUIPMENT.

APPLICATION FILED MAR. 14, 1910.

Patented July '28,

[227ml tons,

m'rnn STATES PATENT OFFICE.

WILLIAM G. BLAU'VELT, or NEW YORK, N. Y., A'ND EDWARD c. MOI-INA, or BLoomrInLD, new JERSEY, nssrenons- TO AMERICAN TELEPHONE AND TELEGRAPH COMPANY, A CORPORATION on NEW YORK.

'rnnnrnounorniiiiron's EQUIP ENT;

Patented July 28, 1914'.

Application filed March 14, 1910. Serial No. 549,151.

To all whom it may concern Be it known that we, VILLIAM G. BLAU- vEL'r and EDWARD C. MOL'INA, respectively residing at New York, borough of Manhattan, and Bloomfield, in the county of New York and countyof Essex, respectively, and State of New York and State'of New Jersey, respective1y,.have. invented certain Improvements in Telephone-Operators Equipment, of which the following is a specification.

Our invention relates to the equipment of telephone; operators, its chiefobjects being to reduce the number of acts and the mental effort required in effecting and S11- pervising a connection between calling and called telephone lines. A saving is also .madein the number of manually actuated,

controlling devices comprised in the operators equipment.

The invention is especially applicable to, and in the single diagrammatic figure of the drawing is illustrated in connection with, a telephone system in which both manual and automatic switching apparatus is employed.

At A is indicatedone of anum'ber of telephone substations joined by its line L to a central station C, at which it terminates in an answering jack J and has associatedwith it the usual line relay R cdntrolling the line lamp'O, together with a cutoff relay R. It also extends to the fixed contacts of a selecting switch, not here illustrated, which may be the last of a chain,., of-;; 'si milar automatic apparatus, the first offwhich is sh0wn.conventionally at S with f'contact brushes 8 driven by motor mechanism M and temporarily retained against restoration to the normal position by a magnet H. The structure and manner of control of such automatic switches is well'understood, and, since our invention is not concerned with these details, they need not be more particularly described. The jack .l' is situated at a particular operating position, which will be provided with a suitable number of connecting or ccrdcircuits 0, one of which is here illustrated, having at one end an answering plug P for cooperation with the jacks J and extending to the brushes of one of the selectors S. Across the main or transmission conductors L and Lof each cord circuit is bridged the central station battery B, between the windings of therepeating coil r. This battery, though it may supply current to all the apparatus of the system, appears in the drawin at various points and is designated by di erent reference characters for convenience description. In the conductor L of the cord circuit are the calling and called line supervisory relays B and R controlling, respectively, supervisory lamps O and O, and in the third conductor L is a relay R the purpose of which will later appear.

Common to all the cord circuits at an operating position is the Ionerators telephone set T and a group K of master keys or like manually operable circuit controlling devices, of which five are illustrated, connected with one another'in series through their resting contacts. One of these keys is may beused to apply at its active contacts current from a source of relatively high potential to one side of theline, to effect in the customary manner the return of a coin deposited in a coin box N at a substation.

When such a key is used, eachcord circuit will include a suitable key K for the purpose of opening said cord circuit and applying to the coin-box mechanism current from a source of opposite polarity to cause the depositof a coin. The remaining keys is of the group K may serve to impress ringing current upon a calling line, where.- by a subscriber may be signaled for the purpose of receiving information, for. example, of the establishment of a desired connection previously impossible. To permit selective ringing over four-party lines four of the keys K2 are shown, these uniting sources of ringing current of opposite sign to both sides of the line.

The operators set, in accordance with the usual practice, is to be-joined through a particular cord with one calling line at a time to enable the subscribersorder to be received, and then separated therefrom and connected to another calling line. It must.

WLNI/ r" also be possible at any time to unite the set with any cord of the operators equipment for the purpose of supervision and to disunite it at will. The master keys K must be actively associated with one of the operators cord circuits at a time, this being the one upon which she is listening-in, but these should. onlyapply the high potential currents to the calling line and'not to the operators telephone or called line. Therefore, the cord should be severed and the keys united only to the answering plug end; To produce an automatic connection and disconnection of the operators set and master keys with respect to the proper cord circuit, they are joined to electromagnetic switching mechanisms, of which there is one for each cord, these being adapted to assume a series ofcircuit controlling positions in regular sequence.

'The-switch D belonging to the cord 0 is illustrated quite fully in the drawing, while a'portion of another switch associated with a cord at the'same operating position appearsat D The form of switching mechanism employed is-not important; that which is here shown'diagrammatically may include a shaft d suitably journaled and carrying fast upon-it a-series ofcams e,'the irregular peripheries of-which cooperate-with springs f to separate them from and force them against-contacts g. Thesecams, springs and contactsa'llflappear in two places in the drawing,in dotted lines in their actual relation'tothe shaft d and in full lines at points most clearly developing the circuit organization: -In the latter case, the cams and contacts are distinguished from one another by numerals afiixed to their reference letters. The switch shaft with its cams may be moved from position to position by a motor magnet m actuating ratchet mechanism. A pulsator -psupplies intermittent current frombattery B through a conductor L to energize the magnet m and thus rotate the shaft, whenever its circuit is completed at oneo'f the contacts of the switch D to ground or other return conductor. This ground connection' may be at someexternal point or localto the switching mechanism itself, the can: (9' controlling the latter condition and determining the correct stopping points'of the switch shaft. When the spring cooperating with this cam is separated from the contact g, this being in the positions indicated by the numerals placed at the opposite side of the spring from th'e'contact,-the projection 11 upon said sprin lies in adepression 12 in the periphery o the cam, and the shaft with the associated cuit of motor'magnet m at some point in the system the projection rides out'of' the depression, and when resting upon the circular-portion' of the cam e closes the local I cams is properly positioned. Upon the completion of the air-1 circuit for the motor magnet, which insures the rotation of the shaft to the next pos1t1on at which the cams are to stop, regardless of external conditions. Thenumerals applied an operating position -arejoined to a common conductor U, which also has a branch leading to a master release or listening out key K the contact of which is ground- .ed. Each cord has individual wit a combined listening-in and listening-out key K, the spring of which'is grounded, while its opposite contacts are connected to similar contacts and 9 of'the switchcam e. The contact g of cam 6 when engaged by it's spring, applies battery to the retaining magnet H of the selector S through the con ductor L The other circuit connections will ap. ear in thefollowing statement of operationof the system.

The subscriber'at-A, desiring to call an other subscriber, removes the receiver from its hook, and the closure of the line from battery B energizes the relay R, lighting the line lamp O. The operator at whose position said lamp is situated responds by inserting the plug P of an unused cord circuit in the subscribers answering jack J. The cooperation of the sleeve of the plug and thimble of the jack completes the circuit of the third conductor L of the cord from battery B energizingthe cut-ofi' relay R to extinguish the line lamp and also causing cord relay R to close its three front contacts. Of these, contact 13 applies battery B to the supervisory lamps, illuminating 0 but not 0 since the calling supervisory relay R has been energized by the closure of the line atsubstation A, breaking its circuit. It will be. evident that the usual action of both supervisory signals is secured. Contact 14 of relay R connects battery B to conductor L, thus exciting the retaining mag net H and preparing the selector S for operation. Contact 15 grounds conductor-L leading to the motor magnet m, pulsator p, andbattery B. through-conductor 16 and contact 9" of switch cam a, closed in the first position. The current impulses through the motor magnet rotate the switch shaft, and "the travel of switch'D is thus started as an incident to an act of the operator (the inserting of plug P in the answering jack J) in connection with the connecting circuit for an. independent purpose. Before switch D leaves its first or normal position, after which the contact is opened, the cam e closes contact g and this locally maintains the stepping circuit until the fifth position is reached, at which contact g opens and the switch stops. In this, the listening position, and in the fourth position, during which presses key Kt.

the switch is traveling the operators set T is bridged acro$5 the cord conductors L and L through conductors 1'? and 18 and contacts g? and g of the cams (2 and e. In

the fifth position the cams e and c? cut into. the cord the entire group K of the maste keys, their contacts g and 9" making the circuit to the keys by way of conductors 18 and 20 before theysever the calling from the ginswe'ring end 0f the ord a the con v is at an end; therefore her telephone set may.

at any time be separated from active association with the cord circuit, 3. This is au-J tomatically effected when the succeeding call is answered. Upon the insertion of the plu of another cord circuit in the answering 13.6 01. a new calling line, similar operations to those just outlined take place in this cord equipment, which includes the switch DF. As soon as this switch leaves its first position, its cam e by the contactg and common conductor L places ound upon the conductor L? of the switc D of the first mentioned vcord, by way which is closed in the fifth position. resultant'intermittent current throu h the motor magnet m starts the switch and its cams e and e at once disconnect the master keys K and close conductors L and L of the cord. In the sixth position the con tact is opened, but ound is now found for the motor magnet t rough contact 9 of earn a conductor 21 and the resting contact of key K. In this position the operators set is cut out of the cord 0 before the switch D? reaches its fifth or listening-in position. Through ositions 7 and 8 the switch 1) travels un' er the control'of the cam e and stops in the ninth or listening-out position.

If the operator wishes to supervise the connection and to againunite her telephone set with some one of the cords from which it has been automatically separated, she In the ninth position the contact 9 is closed, and when the key cooperates with its alternate contact a circuit to ground is provided for the motor magnet m by way of conductors L? and 22. The switch is thereby carried to its tenth position, in which the contact 5 of earn a? is class, and conscguently when hi is released of its contact 5K".

'swering a succeedingv call, she may follow either of two courses, If she as in mind h P ti ula w d, as m gh e he a had she just listened-in by means 9f the yK, h may ac uate th s e kevh switch D being in a different osition from that at which the switch was previously used, this will produce a difierent effeet. Contact g. is closed by the earn e n t e fifth p sition, nd e mp et n of the motor magnet circuit to ground through conductor 22 and actuated key K moves the switch to the sixth position. There the makinghof contact 5; and the restin contact at t e releasedke'y causes the switc to travel to the seventh position, at which it comes; under the influence of the Cam 6 and is carried to the listening-out position. In? the operator has forgotten to which cord her telephone is united she presses the master release key K But one switching mechanism of the operators equipment will in thefifth position, at which the cam c oins the conductors L and L throu h contact 9 The depression of the hey grounds L starting the switch, and through the sixth, seventh and eighth positions the advance is continued by the cams c and 6 to the listening-out position.

I As in the case of the key- ;K, difiorent positions of the switching mechanism lead to difi'erent results when the pin P is removed from the answering jac First, when the condition of the supervisory sig: nals shows that the subscribers have finished their conversation, the operator withdraws the plug from the jack when the swififlh is in its ninth position, Relay R is dener- IQQ 'gized by the opening of the third conductor circuit, extinguishing the supervisory lamps at contact 13, releasin the's'electing app'ae ratus at contact 14: an causing it to be restored to normal, and givinglground for the 139 4 motor magnet of the switc mg mechanism through its back contact 23, conductor 2% and contact 9 0? cam e. As a result of the last mentioned circuit change the switch ing mechanism assumes th tenth position, 1

where ground is applied to conductor Li through the switch contact conductor 21 and the resting contact of the key K. Thi restores the mechanism to its nominal condi;

tien fer a new operation. Second, suppose 18o the operator has selected and rung a wrong substation, she should then communicate with the called subscriber only, apologizing for the error. With the switching mechanismin the listening-in position she withdraws the plug from the answering jack. The circuit of relay R is thus broken, and

as its contact .14 opens, the supply of current for the retaining magnet H of the selector S from battery B is lost, but in the'fifth position contact 9 of the cam e joins battery B, to the conductor L keepin theretaining magnet energized. There ore, the controlling effect of the jack and plug is nullified, and the continuity oi the selective chain is thus maintained. Though relay contact 23 is now. closed, switch contact 9 is open, and the switching mechanism remains inactive and the operators set connected to the called line. Having spoken with the subscriber, the operator may disconnect her set from the cord by use of the keys K or K as already described, but when the ninth position is reached, since relay R is still deenergized, the switch travels on through the ninth and; tenth positions, controlled by the cams c and c to normal. The operator then inserts the plug of a cord in the answering jack of the subscriber who had previously called and her set is automatically reconnected, enabling her to again attempt to secure the desired line.

it the operator finds it necessary, because of some defect, to hold the selective apparatus for inspection by the wire chief, she may place the'p'lugin an extra jack having ground connection to its thimble. This operates relay R? and the magent H therefore remains energized; the operator may then listen-out manually and employ a fresh cord circuit to complete the call. The automatic retention of the connection with the called line, when the answering plug is removed with the switching-mechanism in the listening-in position, not only relieves the operator of a very appreciable drag upon her work, but also reduces her equipment to the extent of a holding key for each cord circuit.

"if the operator, after answering a call and endeavoring to secure a wanted line, finds that-it is busy, she may so inform the calling subscriber, with the statement that a further attempt to complete the connection will be made. The plug is then removed from the jaclr of the calling line. Later when the operator obtains the called line, she plugs into the jack of the calling subscriber with the cord through the selector S of which the desired line has been obtained, and uses the proper master key If to ring-back or again summon to the telephone said calling subscriber. The key atits resting contacts 0 ensthe connection to the operators telep one set and through the conductors 17 and 18 to the called line, the path through the incensecord conductors L and L having been already broken at the switch contacts 9 and 9 Therefore,neither the called subscriber nor the operator sufiers from the effect of the high tension ringing current upon their receivers. The master coin-return key is is included in the cord circuit at all times the operator will find it necessary to employ it, and its manner of useis in ac- "cordance with ordinary practice. The thing which is'to be particularly noted is that by thus employing a set of master keys common to all the cords of an operating posi-' tion, the number of such keys is reduced to operators telephone set normally discon-' nected from the connecting circuit, automatic switching mechanism interposed be: tween the connecting circuit and telephone set and adapted when started to assume a series of circuit controlling positions, in one of which said telephone set and connecting circuit are connected, and means for starting the travel of the switching mechanism, sai

means being operable as an incident to an act o'fthe operator in establishing a connection with the connecting circuit.

2. In a telephone system, telephone lines, a telephone central station,;a connecting circuit thereat, an operators telephone set, automatic switchin mechanism interposed between the connecting circuit and telephone set and adapmd when started to assume a series of circuit controlling positions, and means for starting the travel of the switching mechanism, said means being operable as an incident to an act of the operator in establishing a connection with the connecting circuit said act being prior to the joining of the operators telephone and the telephone line of a calling subscriber.

3. In a telephone system, telephone lines, a telephone central station, a connecting circuit thereat, an operators telephone set, automatic switching mechanism interposed between the connecting circuit and telephone set and adapted when started to assume a series of circuit controlling positions, and means for starting the travel of the switching mechanism, said means being operable as an incident to the act of the operator by which the connecting circuit is joined to the line of a calling subscriber.

4. A telephone system comprising telephone lines and their telephones, connecting circuits therefor, a telephone other than those of said telephone lines, switching mechanisms one individual to each connecting circuit and interposed between its said circuit and said other telephone and havlng a traveling member adapted to assume a mechanism for stopping its movement in a position to unite said other telephone and connecting circuit.

6. A telephone system comprising telephone lines, connecting circuits therefor, a telephone, switching mechanism interposed between the connecting circuits .and telephone,- means controlled by the association of a telephone line and a connecting circuit for starting the switching mechanism from its normal position, means controlled by the switching mechanism for stopping its movemer t in a position to unite the telephone and connecting circuit, means for again starting the switching mechanism to disunite the telephone and connecting circuit, and means for stop ing the switching mechanism before it reac es its normal position.

7. A' telephone system comprising telephone lines, connecting circuits therefor, a telephone, switching mechanisms interposed between the connecting circuits and telephone, means controlled by the association of a telephone line and a connecting circuit for starting a switching mechanism from its normal'position, fmeans controlled by the switching mechanism for stopping its movement in a position to unite the telephone and connecting circuit, and means controlled by another switching mechanism for again starting the previously mentioned switching mechanism.

8. A telephone central station, cord circuits thereat, an operators set for association with said cord circuits, electromagnetic switching mechanisms for the cord circuits respectively each operable to assume a series of circuit controlling positions and in one or more of said positions tojassociate its cord circuit with said operators set, and a relay energized upon the putting of a cord circuit into use and thereby controlling the corresponding switching mechanism 9. A telephone central station, cord circuits theieat, an operators connecting set for association'with said cord circuits, an electromagnetic switching mechanism for each cord circuit, a relay included in each cord circuit and energized upon the putting of said cord circuit into use, and circuits for actuating the switching mechanism closed by said relay and by the switching mechanism of another cord circuit. 7 i

10. In a telephone system, a central rstation, telephone lines extending thereto, connecting circuits for the lines, an operators telephone set, switching mechanism for the operators set movable through a series of circuit controlling positions, means for actuating the switching mechanism to advance the same when a connecting circuit is put into use, and'manually operable means for actuating the switching mechanism to fur ther advance the same.

11. In a telephone system, a central station, telephone lines extending thereto, connecting circuits for the lines, an operators telephone set, switching mechanism for the operators set, said switching mechanism being individual to a connecting circuit, means for automatically actuating the switching mechanism when the connecting circuit is put into use, and manually operable means common to a plurality of connecting circuits for further actuating the switching mechanism.

12. Ina telephone system, a central station, telephone lines extending thereto, connecting circuits for the lines, an operators telephone set, switching mechanism for the operators set, said switching mechanism being movable into a plurality of positions, and means for controlling the movement of the switching mechanism, said means when operated in diiierent positions of the switching mechanism causing its movement to other ditferent positions. p

13. A central. station and telephone lines extending thereto, cord circuits for switching the lines at the central station, an electromagnetic switch associated with each cord circuit, said switch having a normal position, a position in which it connects the operators set with its cord circuit, anda position in which it disconnects the operators set from said cord circuit, a key, circuits closed b the key in the disconnecting positionof the switch for starting the movement of said switch toward its connecting position, and circuits .closed by the key in its connecting position for starting its movement toward the disconnecting position.

14:. Thecombination with a central station and telephone lines extending thereto, of a plurality of cord circuits for said lines each.

central station common to but disassociated from said cord circuits and adapted in its operation to apply current impulses to a ca1ling telephone line, and other automatic means individual to each of said cord circentral office operator for controlling the current in said telephone lines, such manually operable controlling device being common to but normally disassociated from said connecting circuits, and other automatic means individual to each connecting circuit and adapted to perform a series of circuit controlling operations in conjunction therewith one of said operations being the associating of the manually operable device and connecting circuit. y

16.. In a telephone system, telephone lines, automatic selecting apparatus associated therewith, means for connecting the selecting apparatus with a telephone line, a telephone set, means for connecting the telephone set with a telephone line, means controlled by one of said connecting means for causing the restoration of the selecting apparatus, and means governed by the other connecting means for nullifying'said control.

17. The combination with telephone lines, of a connecting circuit and automatic selecting apparatus, an operators telephone set, switches for uniting the connecting circuit with a line and for uniting the operators set with the connecting circuit, means controlled by the line switch for effecting the restoration of the selecting apparatus, and means controlled by the switch for the operators set for preventing the restoration.

18. The combination with telephone lines terminatin in jacks, of operators cord cir-' cuits provi ed with plugs for cooperationwith the jacks, automatic selecting apparatus, an operators set, a sequence switch for connecting the operators set to the cord circuits, means controlled by a jack and plug for causin a movement of the selecting apparatus to normal, and means controlled by'the sequence switch for nullifying the eifects of the jack and plug.

19. The combination with telephone lines terminating in jacks, of operators cord circuits provided with plugs for cooperation with the jacks, automatic selecting appara-- tus, an operators set, a sequence switch for connecting the operators set to the cord circuits, means montrolled by a jack and plug forcausing a movement of the selecting apparatus to normal, and means controlled by the sequence switch in its said connecting position for nullifying the efl'ect of the jack and plug.

20. The combination with telephone lines,

of a connecting circuit therefor, automatic.

selecting apparatus associated with the connecting circuit and including retaining mechanism, means dependent upon the putting of a connecting circuit into use for actuatin the retaining mechanism, and indepen ent means for continuingth actuation of the retaining mechanism.

p 21. The combination with telephone lines, of a connecting circuit therefor, call answering means associated with the connecting circuit, automatic selecting apparatus including retaining mechanism, means for actuating the retaining mechanism upon the connection of the answering means with a calling line, and means for continuing the actuation of the retaining mechanism after the disconnection of the answering mean from the calling line.

22. The combination with telephone lines, of a connecting circuit therefor, automatic selecting apparatus associated with the connecting circuit and including retaining mechanism, means dependent upon the put- Y ting of a connecting circuit into use for actuating the retaining mechanism, a telephone, switching means between said telephone and the connecting circuit, and means controlled by the switching means for continuing the actuation of the retaining mechanism.

23. The combination with telephone lines and answering jacks at which the lines terminate, of a cord circuit provided with an answering plug and with a selecting switch having a retaining magnet, an operators telephone set, means for connecting the op 10 erators set to the cord circuit, a circuit for the retaining magnet closed upon the insertion of the answering plug into the jack of the callingline, and another circuit for the retaining magnet closed by the connecting means. i

24. The combination with telephone lines and answering jacks at'which the lines terminate, of a cord circuit provided with an answering plug and with a selecting switch 11 having a retaining magnet, an operators telephone set, automatic switching mechanism for the operators set, said switching mechanism being capable of assuming a plurality of positions, a circuit for the retaining magnet closed upon the association of the answering plug and jack, and another circuit for the retaining magnet closed by the switching mechanism in one of its positions.

. 25. The combination with a central station 3 and telephone lines extending thereto, of cord circuits, an automatic selector having a retaining magnet, an operators telephone set, automatic switching mechanism for uniting the operators set and cord circuits, and 13; a circuit for the retaining -magnet controlledby said switchin mechanism.

26. The combmation with. a central station and telephone lines extendingthereto, of cord circuits, an automatic selector hav- 13o ing a retaining magnet, an operaltors telephone set, automatic switching rnechanism having a plurality of positions in one of Witnesses:

7 R031. S. SURLIFFE,

ereof, We have signed our SYLVANUS H. COBB.

names to this specification the presence of two subscribing witnesses, this mnth day It of March, 1910. 1

WILLIAM G. BLAUVELT. EDWARD o. MOLINA. 

